Such devices are known and are particularly described in German patent DE-A-41 24 098. In the case of these devices, the hole is generally of a size smaller than the pre-cut portion such that, during pressure exerted by the punching member on the pre-cut piece, the pre-cut piece is deformed within said hole to be ejected from said hole. The problem with such devices is that they generate a certain number of wedgings of the scrap within the hole. These wedgings require stopping the ejection station to free the hole.
In improved devices, the punching member coacts with a resilient abutment member disposed below the pre-cut piece and projecting at least partially into the opening. This abutment member which, in a rest position, is substantially disposed retracted or flush with the separation surface, is adapted to be deformed by spacing from the separation surface during pressure exerted by the punching member on the pre-cut piece, to occupy an inclined position relative to the separation surface. An example of such a device is given in the patent EP-A-446 702. In this case however, it is observed that the scrap is eliminated by sliding of the resilient abutment member. It sometimes happens that the pre-cut piece remains fixed to the punching member. In the case of this device, there is then no possibility to detach the scrap from the punching member. Moreover, it is noted that such a device requires fixing each abutment member by means of a suitable securement member such as a screw. As a result, there is a long and difficult mounting. Moreover, the abutment members used are of complex shape and hence troublesome. Finally, such a device has a large size below the matrix whilst, in all the ejection stations, in general, there exists very little space between the lower surface of the matrix and the rest of the station. Finally, removal of such an abutment member is relatively difficult because of its inaccessibility.